Oh you sweet summer child. Everyone else does this.

Yes, I hate it too.

Put yourself in the position of the employee on the other side. They currently have 647 bugs in their backlog. And they also have actual work to do that's not even related to these bugs.

You come to work. Over night there's 369 emails (after many filters have been applied), 27 new bugs (14 of which are against a previous version). You triage. If you think 8h is enough to deal with 369 emails (67 of which are actionable. But which 67?) and actually close 27 bugs, then… well then you'd be assigned another 82 bugs and get put on email lists for advisory committees.

Before you jump to "why don't they just…", you should stop yourself and acknowledge that this in an unsolved problem. Ignore them, let them pile up? That's not a solution? Close them? No! It's still a problem! Ask you to verify it (and implicitly confirm that you still care)? That's… a bit better actually.

"Just hire more experts"… experts who are skilled enough, yet happy to work all day trying to reproduce these bugs? Sure, you can try. But it's extremely not a "why don't they just…".